Pot type oil burner and pilot means therefor



June 28, 1949. M. D. HusToN l 2,474,530 POT T'PEV OIL BURNER AND PILOT MEANS THEREFOR Filed Aug. 2o, 1945 .2 sheets-sheet 1 56 Rye/daf Mar/@g2 June 28, 1949. M. D. HUsToN POT T/YPE OIL BURNER AND PILOT MEANSv THEREFOR 2 Sheets-Shes?I 2 Filed Aug. 20, 1945 oaoneooeoooweae o ooeoooovooonotee o eooe 9000090009.- s saooaoeoseaeoooe Patented June 28,1949

2,474,530 POT TYPE OIL BURNER AND PILOT MEANS THEREFOR Milton D. Huston, Santa Fe, N. Mex., assignor, by menne assignments, to Breese Burners, Inc., Santa Fe, N. Mex., a corporation of Delaware Application August 20, 1945, Serial No. 611,563

l Claim. l

My invention relates to an improvement in liquid fuel oil burners of the hydroxylating type and has for one purpose to provide improved pilot means therefor.

Another purpose is to provide an improved pilot housing.

Another purpose is to provide a pilot housing which can be readily removed for cleaning when necessary. i

Another purpose is to provide a. pilot housing adapted to maintain the pot bottom highly heated.y

Another purpose is to provide pilot means adapted vfor a rapid and elcient shift of combustion from pilot stage to the high nre stage.

Another purpose is to provide an improved liquid fuel delivering fitting. y

Another purpose is to provide a pilot structure which causes a minimum of interference with the normal operation of a hydroxylating burner pot at high fire.

Other purposes will appear from time to time in the course of the speciiication.

I illustrate the invention more or less diagrammatically in the accompanying drawings wherein:

Figure 1 is a vertical axial section;

Figure 2 is a section on the line 2 2 of Figure l;

FigureV 3 is a partial section on the line 8 3 of Figure 1;

Figure 4 is a view similar to Figure 3 of a variant form of the device;

Figure 5 is a section on the line of Figure fi; and

Figure 6 is a, section on the line G-G of Figure 5.

Like parts are indicated by like symbols throughout the specification and drawings.

Referring to the drawings I generally indicates an outer housing shown in the form of a drum. The outer housing is shown as provided with a plurality of supporting legs 2 which have air admission spaces 3 therebetween. 4 is a centrally apertured bottom wall, its aperture 5 being generally on the axis of the drum l. 6 is a booster ian driven by a motor 1, the motor and booster ian being mounted on any suitable bracket or support 8 which aligns the motor and'fan substantially on the axis of the drum. I is a supporting ring shown as angular in radial cross section. It supports any suitable pot structure generally indicated as I0 and including a circumferential side wall II with an upper out-` wardly extending flange I2 seated on the ring l. The pot is provided with an upwardly concave bottom I l. The otherwise open top of the pot is partly closed by the centrally apertured name ring Il shown as centered by the downwardly extending mange l5. IB is any suitable air protector for the bottom of the pot, aligned with the fan 6. The side wall l I of the pot is provided with a plurality of rows of primary air inlet apertures il located at various distances from the ends of the pot. Any suitable means for admitting secondary air may be employed but for convenience I illustrate a single row of upwardly tilted secondary air inlets Il which are both larger and more closely spaced than the primary air inlets il. I9 is a liquid fuel inlet tting having a longitudinal bore 20 and an intersecting and somewhat larger gauge air inlet vertical bore 2l. The tting is provided with a reduced portion 22 extending through an appropriately formed hole in the lower portion of the pot side wall, and preferably flush with the inner face of said side wall. 23 is an air inlet duct in communication withthe bore 2i and positioned in the space between the drum i and the pot side `wall il. 2d is a T, screw threaded or otherwise secured to the tting I9 and provided with any suitable cleanout member or reamer 25. The lower arm 26 of the T receives any suitable liquid fuel delivery pipe 2l. Any suitable means may be employed for varying the rate of liquid fuel along the pipe 2li and thus through the bore 20 to the interior of the pot. I may employ for example a conventional oat valve assembly, but I illustrate diagrammatically any suitable valve structure 28 with a manual control member 29.- It will be understood however that any suitable means, whether automatically or thermostatically or manually controlled, may be employed.

The pilot structure .proper includes or consists of a pilot housing generally indicated at 30. The housing in Figures 1 to 3 is shown as foraminous. It consists of a curved member, the lower edge of which, as at 3|, surrounds a portion of the pot bottom preferably extending fairly close to the central axis of the pot. 'I'he curved edge portion Il may be connected by straight edge portions 32 with the side wall of the pot. The rear or outer edges 33 of the housing 30 abut against cr conform fairly closely to the side wall of the pot. Preferably a gap I4 is left between an upper edge portion of the housing 30 and the opposed wall of the pot, the gap being atthe top of the pilot structure. The pilot housing 30 is also shown as provided with a laterally extending outwardly turned edge portion- II along each vertical edge thereof, the edge portion llbeing received slidably in any suitable clips 36 welded or otherwise secured to the inner wall `of the pot with clearances permitting ready and generally vertical movement of the pilot housing. Thus the pilot housing can easily be inserted and removed, and can also raise and lower somewhat in response to warping or expansion'and contraction of the bottom I3 of the pot. i

The pilot housing 30 may be employed by itself. I illustrate however a supplemental baille or housing member which may optionally be applied thereto. The outer member, generally indicated as 40, is shown as somewhat similar in form to the housing 30 except that its upper edge terminates at a point inwardly spaced from the pot, as at 4I. Also I find it desirable to have its side edges 42 terminate .inwardly 4from the pot wall, the housing 40 being spaced away from the housing 30. It may for example be mounted on any suitable supporting clips or legs 43. The lower edge of the housing 40 includes the arcuate inner portion 44 and straight edge portions 45. Preferably, as shown in Figure 1, the separation between the members 30 and 40 increases progressively upwardly, the widest gap therebetween being at the top as shown in Figure 1,

Whereas I find it desirable to employ a foraminous pilot housing associated witha foraminous inner baille I mayalso employ a solid pilot housing. Thus in Figures 4 to 6, I illustrate a solid pilot housing 50, of sheet metal, which may be formed identically with the housing 30 except for the employment of a bottom ame outlet or notch 5I which may be unnecessary or'may be omitted when 'a foraminous member is used. The

. solid housing is provided with side lugs 52 which slide in clips 53 corresponding to the clips 35 of Figure 2. I may also employ an outer baille in connection with the solid housing, as shown in dotted lines at 60 in Figure 5.

It will be realized that whereas I have described and illustrated a practical and operative device, nevertheless many changes may be made in the size, shape, numberv and disposition of parts without departing from the spirit of myV invention. I therefore wish my description and drawings to be taken as in a broad sense illustrative or diagrammatic, rather than as limiting me to my precise showing.

The use and operation of the invention are as follows:

I illustrateherein an improved pilot device for liquid fuel burners which permits the operation of the burner'at a very lowturndown while having little or no effect on the top capacity of the burner. It has the further advantage of permitting arapid increase in the rate of ilow of the fuel Without smoking or carbon deposit. In the use of the burner the pilot housing is maintained at red heat and the heat is radiated upon that part of the bottom of the pot which is surrounded by the housing. As liquid fuel flows across the pot bottom it crosses a highly heated area of metal and is also subjected to the radiant heat of the overlying pilot housing. The result is a very bottom down when it warps down slightly. In a sense the housing has a chimney action. but only a restricted chimney action. I preferably employ a top gap 34 or 54 which permits a certain upward circulation of air and vaporized fuel.

However, this circulation is very slight and does not cause an indraft of air from the rest of the interior of Athe pot. The apertures in the pilot housing, vand the air inlet apertures of the pot which communicate with the interior of the pilot housing, are so related as to maintain the pressure within the pilot housing somewhat above that of the rest of the pot interior.

There is a definite relation between the top opening or gap 34 or 54 and the draft at which the burner operates. The smaller the opening is made, the lower the burner can be turned down and still burn clean. If the top opening is too small, the burner .tends to snuff out. The top opening also controls the capacity. In order to burn less oil, the top opening is reduced.

It should be kept in mind that whereas the top opening is desirable and advantageous, it can,

- particularly where a perforated pilot housing is employed, be eliminated entirely. This is possible if the apertures of the pilot housing are large enough and numerous enough.

The pilot housing may be made of perforated material, as in Figures 1 and following, or it may be made of solid metal as in Figures 4, 5 and 6. L If it is made solid, a bottom opening, such as i the notch 5 I, is necessary.

rapid vaporization of the liquid fuel and an ef' `-words the pilot housing is oatingly supported and can be slightly raised by an upwarping of the bottom, andn will gravitationallyfollow the In' designing the pilot housing it is important that the housing cover and surround a substantial area if the pot botom and also that the pilot housing be' so shaped and positioned as to cause a minimum interference with the normal airsupply to that part of the interior of the pot which'is outside of the pilot housing. With reference for example to Figure 5 it will be noted that, in addition to the normal primary air inlets II, seven supplemental air inlets lla are provided in order to increase the supply of air delivered to the interior of the pilot housing. Only ve of the normal primary air inlets communicate with the interior of the housing. Thus, while an ample air supply is provided for the pilot housing, substantially all of the normal primary air inlets are free to direct jets of air, at the high fire, into vaporized fuel present in the interior of the pot outside of the pilot housing. Not merely is an exceedingly small number of jets intercepted but the shape of the housing is such as to furnish no interference with any of the outside jets which are directed radially into theinterior of the pot.

The high temperature maintained by the herein described pilot housing not merely causes a rapid'vaporization of the fuel but prevents tar from forming, and keeps the surrounded pot bottom area clear of carbon.

The expansion -chamber formed between the members 30 and 40, with its upward increase in width, insures that combustion will take place in the space between the members 30 and 4B, instead of at the top. Thus 'the lower portion of the pilot housing is kept highly heated.

Asa-'nove mentioned, supplemental air inlet apertures are provided, as at |1a, in order to ad- .'mit through that part of the sidewall enclosed within the pilot housing a greater 'volume of air than is normally admitted through corresponding areas of the pot wall outside of 'the -pilot housing.

Whereas I 'have' described and shown several different shapes or pilot housing, il will be understood that a wide variation in shape may be made without departing from the spirit of my invention.

One advantage of the pilot housing herein shown is that the size of `the pilot has no relation to the size of the burner. 'I'he same size and shape of pilot element may be employed with burners of different diameter or cubic content.

I claim:

In a liquid fuel burner and pilot means therefor, a burner pot having a circumferential 'side wall, a closed end wall and an open end, said side wall having therein a plurality of air inlets spaced circumferentially thereabout and located at various distances from the ends of the pot, means for delivering a liquid fuel to the interior of the pot upon the end wall thereof at a controlled rate of ow, for vaporization upon the end wall of the pot, and a pilot housing located within the pot surrounding and above that part oi' the end wall of the pot upon which liquid fuel is discharged, the housing includinga. body portion the lower edge of which conforms to the end wall of the pot, the housing wall of which slants upwardly toward and engages and conforms to the inner face of the side wall of the pot,v and an inclined -additional bame body partly surrounding and spaced from the lower portion of the pilot housing and defining, with the pilot housing, an upwardly expanding chamber extending upwardly from the end wall of the pot, such chamber being open upwardly toward the open en'd of the pot.

MILTON-D. HUSTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,975,266 Gambell Oct. 2, 1934 2,162,844 Jenson June 20, 1939 2,179,142 Breese Nov. 7, 1939 2,263,737 Miller et al. Nov. 25, 1941 2,295,799 Focke et al Sept. l5, 1942 2,329,292 Perry Sept. 14, 1943 2,346,816 Breese Apr. 18, 1944 2,355,416 l Breese Aug. 8, 1944 2,357,997 Breese Sept. 12, 1944 2,391,567 Hager Dec. 25, 1945 2,393,176 Livar et al. Jan. 15, 1946 

